Created test code for multiple includes and for using a wrappered portlet request & response in theinclude / forward call
Added negative test cases during a forward or include for the following
request attributes:

javax.servlet.(forward|include).request_uri
javax.servlet.(forward|include).context_path
javax.servlet.(forward|include).servlet_path
javax.servlet.(forward|include).path_info
javax.servlet.(forward|include).query_string

During an include, the xxx.forward.yyy attributes should NOT be present, and
during a forward, the xxx.include.yyy attributes should NOT be present.
Made driver more robust by implementing a retry when a link cannot be
found or cannot be successfully clicked, which is often due to an  exception or other problem that causes an
error screen to be displayed rather than the regular portal page. In this
case, the driver records the page content, accesses the login URL,
and searches for the link again.

Also added a new parameter, 'test.timeout' that allows the timeout in
seconds for page load to be specified. Default is 3 seconds, but by running
the tests with the -Dtest.timeout=N parameter, the timeout can be changed to
N seconds.
Added new dispatcher tests:

* Test that wrappered requests / responses can be used with the
  PortletRequestDispatcher
* Test that the portlet can include multiple servlets during the same
  lifecycle method
* Test that atributes and query string parameters are correctly handled
  during a multi-level include (when an included servlet includes another
  servlet, for example)
corrected some implementation errors in dispatcher tests